PB1916: DETECTION OF AUTOANTIBODIES TO NEUTROPHIL AND ERYTHROCYTE ANTIGENS IN PATIENTS WITH CHRONIC LYMPHOPROLIFERATIVE DISEASES
Authors: Krobinets Irina, Yudina Victoria, Gritsaev Sergey, Sidorkevich Sergey
Journal: HemaSphere (2023)

Topic: 5. Chronic lymphocytic leukemia and related disorders - Biology & Translational Research Background: The course of several lymphoproliferative diseases, especially chronic lymphocytic leukemia (CLL) is often accompanied by immune disorders. Such patients are characterized by pathological activation of immunity with a change in autotolerance and the development of autoimmune disorders. Among the latter, the most famous common are hemolytic anemia, autoimmune thrombocytopenia, but there is very little work there are quite rare articles devoted to neutropenia. To solve the question of the involvement of immune mechanisms in the development of neutropenia and anemia, it is necessary to determine autoantibodies. Aims: Assessment of the frequency of occurrence of autoantibodies to neutrophil and erythrocyte antigens in patients with chronic lymphoproliferative diseases. Methods: Blood samples of 316 patients with CLD: chronic lymphocytic leukemia, hairy cell leukemia, Hodgkin’s lymphomas, non-Hodgkin’s lymphomas, multiple myeloma patients were included in the study. The mean age of patients was 64 years (range, 22 to 84). Granulocyte-specific autoantibodies were detected by the granulocyte immunofluorescence test (GIFT Flow Cytometry). The determination of classes of antibodies directed against RBCs was carried out in a direct Coombs reaction using a gel system DiaMed-ID. Results: The frequency of detection of autoantibodies to neutrophil antigens was 3.4%. Thus, in patients with multiple myeloma, autoantibodies occurred in 2.5% of cases, chronic lymphoid leukemia - in 4.3%, hairy cell leukemia - in 20.0%, Hodgkin’s lymphoma - in 9.1%, non-Hodgkin’s B-cell lymphoma - in 1.5%. The frequency of detection of autoantibodies to erythrocyte antigens was 21.7%. Autoantibodies to erythrocyte antigens were detected in 19.1% of patients with multiple myeloma, in 39.1% of patients with chronic lymphocytic leukemia, in 16.9% of patients with non-Hodgkin lymphoma and in 4.7% of patients with Hodgkin lymphoma. One patient with Hodgkin lymphoma was diagnosed with autoantibodies to both neutrophils and red blood cells. This patient was characterized by a severe course of the disease and the absence of clinical and cytogenetic remission. Changes in autotolerance and the production of autoantibodies in patients with HPPA may be associated with various mechanisms, including impaired T lymphocyte function and pathological presentation of autoantigens by tumor B cells, as well as the secretion of inhibitory cytokines by tumor B cells that alter immune tolerance, enhancing the survival of autoreactive clones. Monotherapy with alkylating antitumor drugs and analogues of purine bases also increases the risk of developing autoimmune neutropenia. Summary/Conclusion: Autoantibodies to neutrophil antigens were more common in patients with hairy cell leukemia and Hodgkin lymphoma. The lowest percentage of antibody detection was observed in non-Hodgkin lymphomas. While autoantibodies to red blood cells were more often detected in patients with CLL and NHL. Keywords: Lymphoproliferative disorder, Autoantibody